


Broken Promise

by gingayellow



Category: Tokumei Sentai Go-Busters
Genre: Alternate Universe, Ex-Borg Jin verse, Gen, M/M
Language: English
Status: Completed
Published: 2013-05-08
Updated: 2013-05-16
Packaged: 2017-12-10 19:36:58
Rating: Teen And Up Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 2
Words: 3,580
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/789386
Author URL: https://archiveofourown.org/users/gingayellow/pseuds/gingayellow
Summary: <blockquote class="userstuff">
              <p>Trek AU! Chief Engineer Masato Jin was assimilated at Wolf 359. When he's eventually found and captured, it's up Ryuuji to save him. Again. Warnings for the themes that come with the Borg, and one-sided suicide pacts.</p>
            </blockquote>





	1. Chapter 1

**Author's Note:**

> For hc_bingo. AU. Prompt is 'death.'

Title: Broken Promise  
Fandom: Tokumei Sentai Go-Busters  
Characters/Pairing: Iwasaki Ryuuji/Jin Masato, Tanba (aka the best character in sentai)  
Rating: PG-13  
Disclaimer: Not mine, anything mentioned here by name isn't mine  
Warnings: One-sided suicide pacts  
Notes: For hc_bingo. AU. Prompt is 'death.'

"Like I told every other curious officer," Assistant Chief Tanba crowed from his desk, "no one is allowed to see the Borg without Captain Tanba's permission."

"Please," Ryuuji insisted. "Just for a moment. He's been in the brig for over a week now, if he was going to break free and assimilate the crew, he would have already."

"The typical arrogance of an engineer!" Tanba smirked/sneered. "I know your kind. You think you can solve anything with equations and gizmos. Well, Chief Shiba knows how to run a tight ship, and I will make her orders are followed exactly--"

"Tanba." Ryuuji smiled serenely. "I'm not sure if you've noticed the ridges on my forehead, but I have them, as does virtually everyone with Klingon ancestry. Now, I'm only half Klingon, but I have inherited some traits, such as being stronger than most Humans." He gave Tanba a pointed look. "I'm certainly strong enough to throw someone into the wall, at least. Not that I would, unless I was angry because my repeated requests were being refused..."

"Point taken." Tanba slouched in his seat. "Five minutes. Then I'm calling the Chief."

"Got it." And it was a little awkward, since he had just threatened poor Tanba, but he wanted to be polite. "Thank you."

\--

Ryuuji had written numerous papers on the Borg. For several years, they were all he could think about. So he had a few ideas what this one might be doing/feeling-- looking for a way to access the Cube, anger, confusion.

This one was just... watching him. Leaning against the wall, as if this was perfectly normal. Like he was perfectly normal.

"You seem to have made yourself comfortable. You were always good at that." The Borg didn't say anything, but he didn't start the 'resistance is futile' speech, either. After one quick glance to make sure that Chief Shiba wasn't sending the bulk of her guards to arrest him, Ryuuji came as close to the force field as he could without getting shocked. "Sempai." It'd been ages since he'd used that word. "Do you remember me at all?"

The Borg remained silent for what felt like forever. Then something flickered in the remaining eye. "Ryuuji." The robotic edge to the voice made Ryuuji shudder internally. "Ryuuji Iwasaki. Human/Klingon. Engineer on the U.S.S. _Gorisaki_." The Borg's mouth twitched. "Your hair is shorter."

"Yes, yes it is!" It was dangerous to get this hopeful, but he couldn't help but feel joy swell up in him. If he remembered something that minute, then perhaps he was still there. He'd seen cases of people being rescued and going back to their lives after being assimilated, perhaps this would be another case. "Do you remember who you are?"

"We are Four of Five," he said without a moment's hesitation.

"No, sempai." Ryuuji had argued in his last paper that it was foolish to try and fight the Borg programming with reminders of the victim's past, and instead go straight to the surgery. Therapy and remembering was for after the implants were taken away. It was strange how easily his own theory was forgotten. "Please remember. Your name is Masato Jin. You and I grew up in Tokyo. We went to the Academy together."

"Of course we remember," and there was an almost bemused note to the Borg's voice, mixed in with the metal. "Masato Jin's knowledge and experience was added to the Collective, not taken away. We also remember that he served on the _Gorisaki_ with you."

"I'm glad." Of course. Of course he'd see it as a list of facts, rather than... he really needed to pay more attention to his own research. "My time with sempai was when I was happiest."

"... We were happy too, Ryuuji."

"Sempai." Ryuuji took several deep breaths before continuing. He had to stay in control, for his sempai. "My new commanding officer, Captain Kuroki, has requested that a surgeon who specializes in the Borg come here. She can help you go back to being Masato Jin--"

"We can't."

"Why not?"

"We know better. We've been Four of Five for years; there is no way to take out all the implants at this point." Despite the bulk of the arm implants, he wrapped his arms around his sides. If he weren't a Borg, Ryuuji would have assumed that he was hugging himself. "We'll always be a Borg. Because you broke your promise."

He really did remember everything. And Ryuuji was clearly not wanted here. "I'm sorry," he said for what good it would do. "I just couldn't lose you."

"Well, you did."

"I know." Suddenly exhausted, Ryuuji lurched to the door. "You must hate me."

For the first time, the Borg turned away from him. "Hate is irrelevant."

\--

"Humph!" Tanba eyed him coldly. "I supposed you've satisfied all your questions. Have more material for another paper, hmm?"

"No." Ryuuji sat in the chair opposite Tanba's desk. "I didn't ask a single question concerning the technical aspects of being a Borg."

"But I thought--"

"Four of Five used to be Masato Jin, Chief Engineer on the Gorisaki. He was brilliant, but difficult to work with because of his eccentricities-- but I'd grown up with him, so I was used to it." It was strange. He'd kept it in for so long, but now he was talking as if he and Tanba were intimate friends. "Then came the battle at Wolf 359."

"... You were at Wolf 359?"

"Yes. Being part Klingon also means I age slower than most Humans." Of course, even if he was now chalk white and more metal than flesh, sempai still looked the same. "Sempai could do his job even when everything was blowing up around him, but he was terrified of the Borg. Not of being killed by them, but being assimilated. Losing himself, his individuality. So," and it was very hard not to cry right now, "the night before we faced the Borg, he forced me to promise that if he was captured, I would kill him before he could be assimilated. I fought him for hours, but he was so determined and so scared..."

"But when the moment came, you couldn't, because he was your friend."

"Yes." Ryuuji looked up at Tanba, who now looked very old. "How did you know?"

"I was at Wolf 359, too. And believe me, your friend wasn't the only one forcing others into that kind of promise." He sighed heavily. "I lost so many friends that day, including Chief Shiba's father. I suppose that's why I'm so protective of her." He smiled a bit. "Well, that and she needs so help with all the ruffians that dare call themselves Starfleet Officers."

Ryuuji smiled back. "Of course. Which reminds me, if you wish to arrest me for disobeying orders and threatening an officer, please feel free." He wouldn't run away from the consequences.

"... No. If it'd been Captain Shiba, I would've done the same thing. And if it'd been Commander Sakurada, I know the Captain would have done the same thing. I'll just conveniently forget this-- but try it again, and I'm tossing you out an airlock, understand? We can't let our feelings get the better of us!"

"Yes, sir." Ryuuji left the office a free person. He went back to his room, going over some of the reports for the day. It was like every other night.

Except sempai was back, but turned into the one thing he truly feared, and now he hated Ryuuji.


	2. Chapter 2

Title: Broken Promise (2/2)  
Fandom: Tokumei Sentai Go-Busters  
Characters/Pairing: Iwasaki Ryuuji/Jin Masato  
Rating: PG-13  
Disclaimer: Not mine, anything mentioned here by name isn't mine  
Warnings: One-sided suicide pacts, body horror, kids making fun of Ryuuji because he's part Klingon in this  
Notes: That Trek AU, which I finally finished. Nergh. Watch out, this one is a little experimental in prose and voice.

_Masato Jin is cutting class when he climbs the stairs to the roof, but he doesn't care. The kid was crying, and if the teacher won't go after him, then he will. "Hello?" The boy is there, hunched up next to an old chair. "Hey, what happened?"_

_The boy wipes at his eyes, and sniffle. "They were making fun of me."_

_Masato Jin frowns. "Why would they..." But the boy lifts his head up, and Masato Jin sees the forehead ridges, and he realizes that this is the Klingon transferring to their school that his mother spoke of. All the kids had been talking about it, wondering if he'd bring a bat'leth to school, or try to kill them. Something bad, since Klingons were bad._

_But Masato Jin's never listened to others, so he sits next to the Klingon. "Are your parents from Chaos, then?"_

_"Kronos. And my father is. My mother was human." The Klingon wipes at his eyes._

_Masato Jin's not very good at comfort, so he decides to try what his grandmother does when he's sad, which is making food. Obviously, he cannot cook here, but he has a bento. "I think we could use a lunch break. Want some?" He opens it. "You probably know this already, since I'm totally famous here, but I'm Masato."_

_The Klingon smiles, a little. "Thank you. And my name's Ryuuji."_

\--

Four of Five didn't want to remember. But he (not we anymore, never again, he's alone now) didn't have the Cube, and all those other wonderfully overwhelming memories and thoughts to drown in anymore. All he had was... himself.

Well, one other person, he realized as the doors swished open. Four of Five froze... but it wasn't him. Good. He supposed.

"Jin." He smiled hopefully/sadly. "Do you remember me?"

He used to be good at feigning indifference. He tried it again for the first time in years. "Commander Takeshi Kuroki. Human."

"It's captain now, actually."

"Really. The Fleet must be doing poorly."

Now Kuroki's smile was all hope. "There's the Jin I remember. Ryuuji was right--"

"Don't mention Ryuuji!"

Kuroki nodded grimly. "Your temper's coming back, too."

"Ryuuji is why I'm like this," Four of Five managed, barely. "And before you even suggest surgeons, I'm an engineer. I know most of the implants can't be taken out after being in me this long, if at all." Four of Five forced himself to keep looking at Kuroki. "I'm always going to be a Borg now."

Kuroki balled his fists. Four of Five knew that when he did that, it was a prelude to yelling. That could only improve their conversation.

But then Kuroki sighed. "My Jin also never gave up, even when things seemed bad." He headed to the door. "Maybe that will come back to you next." And then he was gone, leaving Four of Five to his thoughts.

\--

_"Don't give up."_

_"Well, I don't wanna!" It's Masato Jin and Ryuuji Iwasaki's last year of high school, and they're both trying to figure out the quickest way to be engineers. "And I'd love to work on starships, but..."_

_"You wouldn't be the first cadet with a criminal record," Ryuuji Iwasaki nudges Masato Jin gently, and Masato Jin ignores the heat that rises in his body as a result. "And you should see what some of their most decorated officers have gotten up to."_

_"Maybe. I don't know."_

_"Then let me tell you what I know." Ryuuji Iwasaki gazes at him levelly. "You're brilliant. Starfleet Academy would be making the mistake of a century if they don't accept you."_

_Masato Jin supposes it can't hurt to fill out a form. That's all he has to do, at least at first. "Okay, but you gotta apply with me."_

_Ryuuji Iwasaki smiles. "The second I'm old enough, I will."_

\--

It was then that Four of Five realized just how much he missed seeing Ryuuji smile. He was still angry, of course, but now that he was remembering the happier times, there were things to miss. Ryuuji smiling, being oblivious, nerding out.

He checked the time. It was 0300 hours, Ryuuji was probably asleep. Maybe he would come visit Four of Five in the morning.

Maybe that wouldn't be too bad.

\--

_"Right after orientation, I'll transport my butt back to Tokyo," Masato Jin promises, squeezing Ryuuji Iwasaki's hands. "And I'll come visit every week." It's not good-bye, Masato Jin keeps thinking. He's not saying good-bye to his best friend, because he's coming right back._

_"I know." Ryuuji Iwasaki's eyes are bright. "I'll see you in a few hours."_

_"Right. A few hours."_

_Ryuuji Iwasaki nods, bites his lips-- and then he's kissing Masato Jin, and Masato Jin is kissing him back._

_And when Masato Jin is walking to the shuttle that will take him to San Fransico, he's giggling, because he's got a suspicion that they're gonna do more than kiss after orientation._

\--

Four of Five couldn't get comfortable on the bed. Truthfully, he was still adjusting to the idea of sleeping again in general. After years of recharging in the Cube, sleeping like he used to was proving to be tricky.

It was 0500 hours now. Ryuuji was probably still asleep.

He wondered if Ryuuji still slept only on his back, right in the middle of the bed. That worked out okay though, because he liked to sleep in the corners, curled up in fetal position. The only time they really cuddled in bed was post-sex.

Maybe Ryuuji had found someone new.

... No. No, Ryuuji was more likely to self-torture himself since letting Four of Five down. Which was good. Maybe.

Either way, it was something to ask Ryuuji about if he came back.

\--

_"So," Chief Engineer Masato Jin says as he leans into Ryuuji Iwasaki, "How's my new assistant doing?"_

_"Busy." Ryuuji Iwasaki pokes Jin Masato's stomach with a padd. "And so are you."_

_Masato Jin sighs as dramatically as he can. "Yes, sir." He's about to get back to work, but suddenly there's a very serious looking little boy tugging at his leg._

_"My name is Hiromu Sakurada." He speaks in a very serious tone, too. "I got lost from my sister, and I need help getting home. My father says I can trust the officers on his ship, so take me home."_

_"Wait, Sakurada?" Masato Jin is completely charmed by this situation. "You're the captain's baby! You are so cute, I just--"_

_"Can you help me more than him?" Hiromu Sakurada is talking to Ryuuji Iwasaki now._

_"Yes." Ryuuji Iwasaki takes Hiromu Sakurada by the hand. Jin Masato decides to follow them. Maybe Ryuuji Iwasaki was onto something when he mentioned possibly having kids one day..._

\--

"So much for the kids."

"I'm sorry?"

"Nothing," he assured the doctor. She was sweet, and and very careful not to do anything he'd find unpleasant. He didn't want to like her, but oh well. "Just old memories."

"That's actually a good thing." She took a blood sample. "It means you're getting back to normal."

Four of Five... smiled. Almost. It was still closer to a smile than he has been for years. "Kid, I don't think I'm ever going to be normal again."

She smiled back. "First, calling me 'kid' is incredibly dismissive and sexist."

"Oops, sorry." Now he was grimacing again.

"Second, you're not the first Borg that's come back to their old life."

"What are you..."

She gave him a sympathetic look. "That's right, you were assimilated at Wolf 359, when we still knew very little about the Borg." She took another sample. Four of Five didn't know what of this time. He was an engineer, a lifetime ago, not a doctor. "Since then, Starfleet has encountered the Borg, and in a few instances, people have been rescued."

Four of Five wasn't sure how to react to that, so he settled on feigning indifference. "Doesn't sound like there's a lot of hope."

She shrugged. "Well, maybe you'll be one of the few."

\--

That stuck in Four of Five's mind, even after she left. Few. Apart from the masses. Something he'd prided himself on when he was still a man, something that had been stolen from him when he'd been assimilated, all because of Ryuuji.

Except...

Now that he was away from the Collective, long enough to cobble together a sense of self-- not quite Masato Jin, not quite Four of Five-- he remembered. Not like the flashes he'd been having, but genuinely remembering the night before Wolf 359. He and Ryuuji had been working on the engines for what felt like forever, getting an exploration vessel ready for war, but then Sakurada told them to rest.

Which had only given him time to further research what the Borg did to people. He'd been reading nothing but that since the damn thing started, but he'd become obsessed. Obsessed enough to ask-- beg Ryuuji, that if they came on the ship like they had with the _Enterprise_ , to not let him be taken, no matter what.

Ryuuji had refused. Ryuuji tried cajoling, reassuring, screaming, crying, begging himself, because _I don't want to kill my sempai, why is that so hard to understand?_ And now it made him sick with shame, because he'd hurt Ryuuji, but he'd kept saying _It's worse than death. Please. Don't let them get me._

And finally, Ryuuji took a shuddery breath, and said, _Fine. I promise if the Borg try to assimilate you, I'll kill you first. But only because I refuse to let them assimilate you."_

\--

_The Borg grabs him, and injects him with something. He feels cold. "Ryuuji--"_

_Ryuuji Iwasaki's face contorts in terror, and he waits for his kouhai to end it. To set him free._

_But he instead roars in fury, killing the Borg that assimilated him. Then another, but the remaining three have adapted. Ryuuji chases after them, but they transport him to the Cube-- so Masato Jin's/Four of Five's knowledge can help them later-- before anything else happens._

\--

"I'm sorry, Ryuuji," he says to himself. He'd been so scared. And Ryuuji had been too, but he kept fighting for him, no matter what. And then he'd said those awful things to Ryuuji!

He had to fix it.

Luckily, Jin was good at fixing things.

Or breaking them, as in this case undoing the lock and (gently) knocking out the guard.

\--

It was late, and there were only a few civilian engineers and teens up past curfew to greet Jin. And they were too busy running away from the Borg to try and stop him.

"Sorry, I'll email you an apology!" He shouted to the girl who bolted past him. But for now, he focused on undoing the lock to Ryuuji's room. "Hey, Ryuuji, I'm back!"

... And Ryuuji was aiming a phaser at him, but who could blame him. "No, no, I mean I'm back! I am, as in singular, as in Jin!"

He didn't stop aiming the phaser, but Ryuuji's lips twitched. "... Sempai?" 

"Yeah. And Ryuuji, I'm really sorry, I should have never forced you into that kind of promise."

"No, no, no, there's no need to apologize, you were scared." Ryuuji took a step to him. That was a step in the right direction, as far as Jin was concerned. "But please understand that I couldn't do it, you're too dear to me, and--"

"Don't worry. I get it. I had a lot of time to think." And he smiled, and it was easier this time. "And I think I'm ready to try the operation that makes me as normal as possible."

Ryuuji nodded tearfully. "We'll schedule you right away-- Hiromu, no!"

Jin turned, and a young man was pointing a phaser at him. "Back off, Borg."

"Wait... is that Sakurada's little boy?" It was, he recognized the jawline. "Don't worry, I'm a good Borg now!" He started to walk to Hiromu. "And you are still as adorable as ever--"

Hiromu stunned him.

\--

"Sorry," Ryuuji said yet again. "Hiromu has a thing about the Borg."

"Don't blame him." Jin decided to not even try sitting up. "I don't suppose his dad was assimilated, too?" Because maybe... after all, he'd been rescued...

"Captain and Doctor Sakurada were killed at Wolf 359."

"Damn."

"Damn indeed." He squeezed Jin's hand, wires and all. "It's selfish of me, but I'm so glad you're safe."

"It's not." Jin squeezed back. "Thanks for waiting for this stubborn old man." Then he took a moment, because he didn't want to appear nervous about the operation. "Will you wait just a bit longer, until after she's done?"

Ryuuji smiled. "Always."

\--

He woke up slowly, then looked at his right hand. It was still almost all Borg, as well as his arm. He still feel the old sensors in his legs and back, and in his brain. He went to feel the bit of metal at his left temple... but stopped to stare at his left hand. It was normal. And the parts of him that still had skin were back to their old color. His hair... was a heart-breaking buzz cut, 'thanks' to the brain surgery, but hair grew. Human hair grew.

Feeling more like himself than he had in years, he called out for Ryuuji.

And this time, nothing stopped Ryuuji from joining him.


End file.
